Ask HN: Python development on Ubuntu best practices

I'm typically a developer on Windows, and I've done a decent amount of Python on Windows.

My workflow is I install the version of Python needed, we're on 3.5/3.6 so we stay pretty current, then use venv and install all my dependencies.

When using Linux I've read I really don't want to use my system Python, even if it happens to be the correct version.

With Ubuntu specifically, and its package manager, how do I install a different version of Python or how do I de-couple Python from the OS?

It would be simple to create some sort of virtual environment and install the requirements inside it but I want to make sure I'm doing the right thing from the start.